1. Field of the Invention
The present invention relates to a self-propel system for driving a high-rail vehicle along railroad tracks. More specifically, the present invention relates to an apparatus for driving the vehicle along railroad tracks from a location remote from the cab eliminating the need for an additional operator during railroad track maintenance as well as a novel system for depositing tie plates along the track.
2. Description of the Related Art
Railroad tracks generally consist of two parallel steel rails, which are positioned on transverse railroad ties. Railroad ties are normally laid on a bed of coarse stone known as ballast, which combines resilience, some amount of flexibility, and good drainage characteristics. Railroad ties spread the load from the rails over the ballast, and substrate below, and also serve to hold the rails a fixed distance apart. The railroad ties are generally spaced apart a distance of about twenty-two inches on center although the distance may vary. On an upper surface of the railroad tie, is a tie plate or base plate. The tie plate connects the rail and the tie. Fasteners, such as spikes, screws or the like are often driven through a hole in the tie plate to hold the rail. Alternatively the rails may be clipped to the tie plates.
The steel rails can carry heavier loads than any other material. The rails generally have a foot, a web extending upwardly from the foot and a head. Additionally, the rails are spaced apart a preselected distance corresponding to wheel spacing of trains. The preselected distance between rails is known in the art as the gauge distance.
Over time, deterioration and repeated loading stress requires that the railroad tie plates, as well as other components, be replaced during maintenance. Various machines which deliver and position railroad tie plates along a railroad track bed have been suggested. One problem with these devices is that they require multiple workers to operate. For example, one person is required to drive the vehicle along the tracks, another person is required to operate a crane to retrieve tie plates, and at least two other men are typically required to position and orient the tie plates on the feed system. Since profitability in this work is related to the number of men required to perform the job, a decrease in man power leads to increased profits, assuming no change in tie plates distributed.
It would be highly desirable to provide a device which allows for elimination of one or more workers on railroad maintenance crew, without a decrease in production or the number of tie plates distributed. It would also be desirable to provide a system which allows for control of the high-rail vehicle along a railroad track from a remote position on the vehicle, away from the cab, where an operator can also perform other tasks.
Another problem with current tie plate distribution systems, is that various systems rely on timing or distance measurements to distribute tie plates. For example, the prior art devices may utilize geared timing mechanisms which deposit tie plates based on a distance traveled. The gears or sprockets need only be adjusted when distributing tie plates on a track having different tie spacing. These assemblies for depositing railroad ties use measurement or timing mechanisms to deposit tie plates regardless of whether the actual railroad tie is beneath the distribution system. Over long distances or periods of time, tie plates may not be deposited on the ties, but instead between them. This is due to mechanical tolerances which are magnified over periods of time or distance and therefore require adjustment when such timing is off.
It would be desirable to positively detect the location of an existing tie plate and cause the depositing of a replacement tie plate at that location along the railroad track, rather than approximate a position of a railroad tie by distance or timing.
One additional problem with tie plate distribution systems is that of conveyor systems which receive tie plates from the high-rail vehicle and deposit them on the railroad ties. These conveyors are typically formed of conveyor belts or roller conveyor systems. Over time, belts and idler rollers may wear, become soiled with dirt and contaminates, or break such that conveying is inhibited which ultimately decreases efficiency and therefore increases costs in railroad maintenance.
It would be desirable to create a tie plate slide which does not require the use of belts or rollers that may become damaged and require maintenance during the life of the equipment.